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(Ph o-C), 129.2 (Ph m-C), 126.9 (Ph p-C), 123.2 (Dipp m-C), 122.9
(Dipp p-C), 43.0 (N–CH2–), 36.8 (Ph–CH2–), 28.8 (CH(CH3)2), 24.2
(CH(CH3)2). MS (DEI): m/z (%) 308 (40, [M]+), 265 (25, [C18H21N2]+),
volatiles were removed in vacuo and the precipitate was suspended
in toluene (3 mL). The suspension was filtered and after addition of
n-pentane (4 mL), THF (1 mL) and 18-crown-6 ether (193 mg,
203 (10, [C13H19N2]+), 188 (80, [C12H16N2]+), 172 (15, [C11H12N2]+), 0.73 mmol), 89 mg of 11 (20 %) were isolated as orange crystals at
161 (45, [C10H13N2]+; [C11H15N]+), 146 (25, [C11H14]+; [C10H12N]+), 130
(20, [C10H10]+; [C9H8N]+), 104 (20, [C8H8]+; [C7H6N]+), 91 (100, [C7H7]+;
5 °C. Physical data show cocrystallized THF (0.5 equiv.). M.p. 180–
185 °C (dec.). 1H NMR (C6D6, 297.0 K, 600.15 MHz): δ = 8.40–8.38
[C6H5N]+), 78 (5, [C6H6]+), 65 (5, [C5H5]+), 39 (10, [C3H3]+), 29 (20, (m, broad, 2H, Ph o-CH), 7.34 (d, JH,H = 7.8 Hz, 2H, Dipp m-CH),
3
[C2H5]+); IR (pure, ν/cm–1): 3203 (w), 3058 (w), 3027 (w), 2957 (m),
7.27–7.22 (m, 3H, Ph m-CH, Ph p-CH), 7.19 (d, JH,H = 7.2 Hz, 1H,
3
˜
2928 (m), 2866 (m), 1661 (s), 1629 (m), 1603 (m), 1584 (m), 1495 Dipp p-CH), 4.36 (s, broad, 1H, NH), 3.61–3.58 (m, 2H, CH(CH3)2),
(w), 1479 (w), 1461 (m), 1452 (m), 1428 (m), 1398 (m), 1381 (m), 3.57–3.56 (m, 2H, thf O–CH2–), 3.22 (s, broad, 24H, 18-crown-6 O–
3
3
1362 (m), 1324 (w), 1306 (w), 1256 (m), 1235 (m), 1187 (m), 1157
(m), 1070 (w), 1057 (w), 1028 (w), 991 (m), 935 (w), 831 (w), 793 (m),
779 (m), 769 (m), 746 (s), 701 (s), 662 (m). Elemental anal. (C21H28N2,
308.46): Calcd.: C 81.77, H 9.15, N 9.08; found C 81.64, H 9.12, N
9.09.
CH2–), 1.42 (d, JH,H = 6.6 Hz, 6H, CH(CH3)2), 1.38 (d, JH,H = 6.6 Hz,
6H, CH(CH3)2). 13C{1H} NMR (C6D6, 297.0 K, 100.62 MHz): δ = 158.2
(NC(Ph)N), 149.9 (Dipp i-C), 140.9 (Dipp o-C), 123.1 (Dipp m-C), 121.3
(Dipp p-C), 70.4 (18-crown-6 O–CH2–), 67.8 (thf O–CH2–), 28.9
(CH(CH3)2), 25.8 (thf –CH2–), 24.3 (CH(CH3)2), 24.0 (CH(CH3)2). MS
(DEI): m/z (%) 318 (10, [M-18-crown-6), 303 (10, [C18H20KN2]+), 280
(30, [C19H24N2]+), 264 (15, [C18H20N2]+; [C19H22N]+), 248 (10,
[C18H18N]+; [C17H16N2]+), 237 (20, [C16H17N2]+; [C17H19N]+), 221 (5,
[C16H15N]+; [C15H13N2]+), 203 (5, [C15H9N]+; [C13H19N2]+), 177 (100,
[C12H19N]+; [C13H7N]+), 162 (95, [C12H18]+), 146 (10, [C11H14]+), 133
(10, [C6H13O3]+; [C10H12]+), 120 (10, [C7H8N2]+), 103 (35, [C7H5N]+),
89 (15, [C4H9O2]+), 73 (10, [C4H8O]+), 59 (5, [C3H7O]+), 45 (25
General Procedure for the Synthesis of Potassium Amidinates
1–7, 9 and 10: Potassium bis(trimethylsilyl)amide was dissolved in
toluene. This solution was added dropwise to a solution or suspen-
sion of the corresponding amidine or formamidine in toluene or
tetrahydrofuran (in cases when the amidine is completely insoluble
in toluene). The reaction mixture was stirred 16 h overnight at r.t.
If the amidinate was insoluble in toluene the product was filtered
using a Schlenk frit. The crude product was extracted three times
using n-pentane. If the amidinate is soluble in toluene, the solvent
was removed in vacuo and the residue extracted three times with
n-pentane. If required the complexes were recrystallized from a mix-
ture of toluene and 1,2-dimethoxyethane or tetrahydrofuran. The
crystallization was initiated by diffusion of n-hexane into the satu-
rated solutions of the complexes. The final product was dried in
vacuo. For further preparative details and physical parameters see
the Supporting Information.
[C2H5O]+), 39 (15, [C3H3]+), 28 (20, [CH2N]+). IR (pure, ν/cm–1): 2956
˜
(w), 2863 (w), 1641 (w), 1611 (w), 1573 (w), 1499 (m), 1426 (m), 1378
(w), 1351 (m), 1326 (w), 1250 (w), 1103 (s), 1025 (w), 961 (m), 882
(w), 856 (w), 838 (w), 783 (w), 745 (m), 698 (m), 648 (w). Elemental
anal. ([C31H47KN2O6]·0.5C4H8O, 618.86): Calcd.: C 64.05, H 8.31, N
4.53; found C 63.58, H 8.36, N 4.36.
[K{Dipp–N=C(Ph)N–C2H4–Py}]n (12): A solution of benzamidine
Dipp–N=C(Ph)–N(H)–C2H4–Py (235 mg, 0.61 mmol) in THF (2 mL)
was added to a suspension of KH (38 mg, 0.95 mmol) in THF (10 mL)
at r.t. and the reaction mixture was stirred for 16 h. Thereafter the
mixture was filtered and all volatiles were removed in vacuo. Color-
less crystals of 12 (78 mg, 28 %) were isolated after recrystallization
from a mixture of THF and toluene (1:1) and drying in vacuo. Identi-
cal analytical data were obtained using KN(SiMe3)2 or benzyl potas-
sium as metalation reagent. Physical data show cocrystallized THF
(0.5 equiv.), which is partly lost during drying in vacuo. M.p. 156–
[(thf)K{Dipp–N=C(H)-N–C2H4–Ph}]2 (8): A solution of formamidine
Dipp–N=C(H)–N(H)–C2H4–Ph (300 mg, 0.97 mmol) in toluene
(7.5 mL) was added to a solution of KN(SiMe3)2 (250 mg, 1.27 mmol)
in toluene (7.5 mL) at r.t. and the reaction mixture was stirred for
24 h. All volatiles were removed in vacuo. The residue was sus-
pended in THF (3 mL) and filtered. Storage of the filtrate at –20 °C
for several days led to the formation of 100 mg of 8 (25 %). Drying
1
159 °C (dec.). H NMR ([D8]THF, 299.1 K, 300.19 MHz): δ = 8.41 (m,
1
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in vacuo caused partial loss of ligated ether. M.p. 127 °C (dec.). H
1H, Py N–CH), 7.58 (t, JH,H = 7.8 Hz, 1H, Py m-CH), 7.22–7.12 (m,
NMR ([D8]THF, 297.0 K, 400.13 MHz): δ = 7.76 (s, 1H, NC(H)N), 7.27–
7.07 (m, 5H, Ph o-CH, Ph m-CH, Ph p-CH), 7.01 (d, 3JH,H = 7.6 Hz, 2H,
Dipp m-CH), 6.92–6.89 (m, 1H, Dipp p-CH), 3.65–3.62 (m, 1H, thf O–
7H, Har), 6.84 (m, 2H, Har), 6.68 (m, 1H, Har), 3.80 (m, 2H, N–CH2–),
3.64–3.61 (m, 1H, thf O–CH2–), 3.14 (m, 4H, CH(CH3)2), Py–CH2–),
3
1.80–1.76 (m, 1H, thf –CH2–), 1.10 (d, JH,H = 6.6 Hz, 6H, CH(CH3)2),
3
0.93–0.91 (m, 6H, CH(CH3)2). 13C{1H} NMR ([D8]THF, 297.0 K,
100.62 MHz): δ = 150.1 (Py N–CH), 139.1 (Dipp o-C), 136.9 (Py m-C),
129.1 (Car), 128.4 (Car), 124.1 (Car), 123.0 (Car), 121.8 (Car), 39.2 (Py–
CH2–), 29.1 (CH(CH3)2), 26.6 (thf –CH2–). MS (DEI): m/z (%) 385 (100,
[L]+), 342 (65, [L-C3H7]+), 292 (15, [C20H24N2]+), 279 (20, [C19H23N2]+),
264 (60, [C18H20N2]+), 235 (50, [C16H15N2]+), 206 (15, [C15H12N]+), 106
(70, [C7H8N]+), 93 (15, [C6H7N]+), 79 (10, [C5H5N]+), 65 (< 5, [C5H5]+),
43 (5, [C3H7]+). MS (Micro-ESI pos. in THF + MeOH): m/z (%) 386
CH2–), 3.48–3.42 (m, 4H, N–CH2–, CH(CH3)2), 2.73 (t, JH,H = 8.0 Hz,
3
2H, Ph–CH2–), 1.79–1.76 (m, 1H, thf –CH2–), 1.14 (d, JH,H = 6.8 Hz,
12H, CH(CH3)2). 13C NMR ([D8]THF, 297.0 K, 100.62 MHz): δ = 169.4
(NC(H)N), 148.0 (Dipp i-C), 144.3 (Dipp o-C), 142.0 (Ph i-C), 129.4 (Ph
o-C), 128.9 (Ph m-C), 126.3 (Ph p-C), 123.2 (Dipp m-C), 123.2 (Dipp
p-C), 68.3 (thf O–CH2–), 53.7 (N–CH2–), 41.6 (Ph–CH2–), 28.4
(CH(CH3)2), 26.4 (thf –CH2–), 24.8 (CH(CH3)2). MS (DEI): m/z (%) 347
(5, [KL]+), 308 (5, [L]+), 188 (5, [C12H16N2]+), 161 (3, [C10H13N2]+;
[C11H15N]+), 92 (5, [C7H8]+; [C6H6N]+), 39 (100, [C3H3]+). IR (pure,
(100, [L + H]+), 264 (10, [C18H20N2]+). IR (pure, ν/cm–1): 3281 (w),
˜
ν/cm–1): 3058 (w), 3027 (w), 2957 (m), 2928 (m), 2866 (w), 1663 (m),
˜
3241 (w), 3215 (w), 3138 (w), 3040 (w), 2952 (w), 2924 (w), 2865 (w),
1621 (w), 1596 (w), 1533 (w), 1459 (w), 1441 (w), 1378 (w), 1356 (w),
1338 (w), 1313 (w), 1299 (w), 1279 (w), 1256 (w), 1244 (w), 1144 (w),
960 (w), 879 (w), 784 (w), 774 (w), 758 (w), 727 (w), 714 (w), 694
(w), 680 (w), 667 (w), 655 (w), 641 (w), 616 (w), 595 (w), 581 (w),
568 (w), 555 (w), 533 (w), 501 (w), 491 (w). Due to the sensitivity of
this compound toward moisture and air during handling and
weighing no reliable CHN analytical data were obtained.
1641 (w), 1629 (m), 1584 (w), 1462 (w), 1451 (w), 1428 (w), 1381
(w), 1257 (m), 1237 (m), 1187 (w), 1157 (m), 1097 (w), 989 (m), 957
(m), 843 (m), 831 (m), 805 (m), 792 (m), 779 (m), 768 (m), 746 (m),
701 (m), 664 (m), 637 (m), 497 (m). Elemental anal. ([C25H35KN2O]2,
836.48): Calcd.: C 71.72, H 8.43, N 6.69; found C 70.80, H 8.44,
N 6.75.
[(18-crown-6)K{Dipp–N=C(Ph)–N(H)}] (11): A mixture of amidine
Dipp–N=C(H)–N(H)–C2H4–Py (301 mg, 0.78 mmol) and KN(SiMe3)2
(160 mg, 0.80 mmol) was stirred in THF (9 mL) at 45 °C for 26 h and
[(EtO2)0.5K{Tripp–N=N–N–C2H4–Py}]2 (13): A solution of triazene
Tripp–N=N–N(H)–C2H4–Py (200 mg, 0.57 mmol) in Et2O (4 mL) was
the conversion was monitored by NMR spectroscopy. Thereafter all added to 34 mg (0.85 mmol) of KH in Et2O (4 mL) at r.t. and the
Eur. J. Inorg. Chem. 0000, 0–0
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